Packing for turbine-shafts and the like.



PACKING FOR TU IIIIIIIIIIIIIIIIIIIII E.

A P P L l C A T l 0 N F l L E D A U G 9 I 9 I 8.

Ffiowzea z m/w W. F. SOMES.

' PACKING FOR TURBINE SHAFTS AND THE LIKE.

APPLICATION FILED AUG-9. I918. 1,308,454, Patented July 1, 1919.

2 SHEETS-SHEET 2.

Z064 ZZ'e v ii 54:2 E76 6 a i j 'ITED STATES PATENT OFFICE.

WALTER F. SOMES, F BOSTON, MASSACHUSETTS.

PACKING FOR TURBINE-SHAFTS AND THE LIKE.-

isomer.

Tn packing turbine shafts it has been cus tomary to employ a pluralityof rings made up of segments, the rings being disposed side by sidewithin the wall of the turbine casing with their juxtaposed facesbearing tightly against each other so as to prevent steam from passingtherebetween. These segmental rings are diflicult to manufacture andadjust, and what is more serious in turbine practice is thatthe highsteam .pressure within the turbine forces these rings so tightlytogether that. the wear between the juxtaposed surfaces of therespective rings is excessive.

The principal object of the present invention is to provide a packingfor steam turbine shafts and the like in which the bearingmembers arenot forced together by the steam pressure so as to produce undue wear.This object is attained by arranging the packing members so that themembers are subjected to no unbalanced steam longitudinally of the shaftOther objects of the invention will be apparent from the followingdescription and accompanying drawings, in which,

Figure 1. is a longitudinal central section of one embodiment of myinvention;

Fig. 2 is a transverse section on line 22 of Fig. 1;

Fig. 3 is a'central longitudinal section of another embodiment of theinvention; and

Fig. 4 is a transverse section on the line 44 of Fig. 3.

In Figs. 1 and 2 T have illustrated my invention as being applied to aturbine, 1 representing a turbine casing, and 2 the turbine shaft. Thepacking is mounted in a cap 3, which is secured to the end of the easing1 by means of stud bolts 4.

The embodiment of my invention illustrated in Fig. 1 comprises a sleeve5 which is secured to the shaft 1 in any suitable Specification ofLetters Patent.

pressure Patented July 1, 1919.

Application filed August 9, 1918. Serial No. 249,050.

manner as by a pressed fit, key connection, by belng formed integrallywith the shaft, or by means of a set-screw such as illustrated at 6 inFig. 1. The sleeve 5 extends beyond the end of the cap 3 and at itsouter end is provided a packing of any suitable type, as for example theordinary packing illustrated in Fig. 1 which comprises packing material7 confined in an annular recess between the end of the sleeve 5 and thecap 8. v

, The main packing joint is between the rings 9 and 10, which arepreferably formed ofbabbitt and cast iron respectively. These rings arecontinuous and their contacting surfaces are preferably curved frominside to outside, as shown in Fig. 1. The ring 10 is prevented fromrotating by means of pin 11 or in any other suitable manner. The sleeve5 is providedwith a flange 12 near its inner end and the ring 9 isprovided with a flange 13 ,which extends over the flange 12. A packing14 of any suitable type is preferably provided between the flanges 12and 13, as illustrated for example in Fig. 1.

The ring 9 is arranged to rotate with the sleeve5 and this may beeffected in any suitable manner, as for example by means of pins 15projecting from the flange 12 into the sockets 16 in the ring 9. Springs17 are provided in sockets in the ring 9 to engage the. flange 12 andyieldingly urge the ring- 9 against the ring 10. Any suitable number ofpins 15 and springs 17 may be employed, the pins and springs beingsuitably spaced about the shaft, and if desired the pins and springs maybe disposed in the same sockets with the pins extending along 'the axesof the springs. In order to lubricate the contacting surfaces betweenthe rings 9 and'lO a lubricant cup 18 is arranged to communicate withthe space between the rings \9 and 10 through pipe 19 and a duct 20extending lengthwise through the ring 10. The ring 10 and flange 12 havethe same external diameter so that the steam pressure existing in thespace 21' exerts equal and opposite forces on the opposite ends of ring9 inasmuch as theefi'ectlve end areas 22 and 23 of the ring 9 which areexposed to the steam pressure are equal,

of steam through this space. Inasmuch as the ring 9 rotates with thesleeve 5 there is very little danger of steam escaping between theflanges 12 and 13, so that asmall packing of the ordinary type such asshown at 14 is adequate to prevent loss of steam through this space.Inasmuch as the ring 10 does not rotate relatively to the cap 3 it maybe secured to the cap sufficiently tightly to prevent the escape ofsteam between these two parts. a

The main packing joint, therefore, is the "joint between rings 9 and 10.This joint is kept tightly closed by means of the springs 17. However,the pressure between the rings 9 and 10 is not rendered excessive by thesteam pressure in the space 21 around the rings for the reason that theeffective areas of the opposite ends of the ring 9 which are exposed tothe steam pressure are equal. Oil or grease is supplied to the maincontacting surfaces between rings 9 and 10 from cup 18 through pipe 19and duct 20. By making the contacting surfaces of the rings 9 and 10radially curved in the manner shown the parts will automatically adjustthemselves more closely together than if they were tapered or madeperpendicular to the axis ofthe shaft and the curvature also tends toprevent the oil or grease from. being; thrown outwardly from the spacebetween the rings. It will be understood that-the end thrust on shaft 2,if any, will be taken up in the ordinary manner by thrust bearings notshown.

' The embodiment shown in Figs. 3 and 4 comprises a turbine'casing 31and turbine shaft 32, a cap 33 secured to the end of the casing 13 bymeans of stud bolts 34, a col lar 35 fastened to the shaft 32 in anysuitable manner, as by being formed integrally therewith as shown inFig. 3, two main bearing rings '36 and 37 formed of. anysuita'ble'bearing materials, as for example cast iron and babbitt respectively, anauxiliary cap 38 secured-to the outer end of the main cap 33 by studbolts 39, and a lubricant cup 40 communicatin fwithuthe space betweenrings36 and 37 through pipe 41 and duct 42. As shown in Fig. 4, the maincap 33 is approximately elliptical in cr0sssection,

' while the auxiliary cup 38'is circular. The

ring 36 is arranged to rotate with the shaft 32 and for this purpose Ihave shown a pin 43 extending from collar 35 into an openm in ring 36,although it will be understoo that the ring '36 maybe otherwise securedto collar 35, that may be urged against like comprising a packing ri thering 37 by means of springs such as spring 17 in Fig. 1, and that itmay, if desired, be provided with a flange such as flange 13 in Fig. 1overhanging the collar 35. The ring 37 is prevented from rotating bymeans of the pin 44 and is urged against the ring 36 by means of springs45. The pipe 46 is preferably arranged to slide in an opening throughthe auxiliary. cap 38 as the ring 37 moves axially with respect to theauxlliary cap .38. -A packing 46 of any suitable type is providedbetween the ring 37 and the surrounding casing. Clearance is-providedbetween rings 36 and 37 and shaft 32 to permit the rings to adjustthemselvesito each other.

The operation of the embodiment shown in Figs. 3 and 4 is similar tothat of Figs. 1 and 2. However, instead of yieldingly urging theinnerring against the outer ring as in Fig. 1 the outer ring 37 is urgedagainst the inner ring 36 in Fig. 3. The end thrust on shaft 32, if any,is taken up by the ordinary thrust bearings not shown, and it will beobserved that there is no unbalanced end thrust produced on the ring 36by steam pressure, inasmuch as it is disposed between the collar 35 andthe ring 37 which are of equal external diameter.

Considerable clearance is provided between pinsll, 15, 43 and 44 andtheir cooperating recesses to permit relative movement of the bearingrings for the purpose of automatically adjusting the curved bearingfaces of the rings tightly together.

From the above it will be apparent that there is no unbalanced steampressure acting longitudinally on the rotating packing ring. The steampressure acting on the packing rings therefore does not add to thefriction between the relatively moving parts of the packing. Moreover,the packing rings are continuous and not segmental.

In certain of the claims I haveused the term gas pressure generically toinclude both air pressure and steam pressure.

1. A packing for turbine shafts and the like comprising a packing ringrotatable with the shaft, and a non-rotatable packing ring fittingagainst the rotatable ring so as to prevent steam. from escapingtherebetween, the rotatable ring being balanced longitudinally of theshaft with respect to steam pressure thereon.

2. A packing for turbine shafts and the rotatable with the shaft, and anon-rotata) 'le packing ring fitting againstthe rotatable ring so as toprevent steam from escaping therebetween, both of said rin beingbalanced longitudinally of the sha with respect'to gas pressure thereon.I

. 3. A packing for turbine shafts and the like comprising a packing ringrotatable with the shaft, anda non-rotatable ring having a side facefitting against a side face of the rotatable ring so as to prevent steamfrom escaping therebetween. the rotatable ring being arranged to beSubjected to no unbalanced steam pressure longitudinally of the shaft.

t. A packing for turbine shafts and the like comprising a packing ringrotatable with the shaft. and a non-rotatable packing ring fittingagainst the rotatable ring so as to prevent steam from escapingtherebetween. the rotatable ring having equal and opposite end facesexposed to the steam pressure so that the steam pressure thereon isbalanced longitudinally of the shaft.

2 A packing for turbine shafts and the like comprising a collar fast tothe shaft, a non-rotatable packing ring, and a packing ring interposedbetween said collar and said non-rotatable ring with its end facefitting against the end face of said non-rotatable ring. said collar andnon-rotatable ring having substantially the same external diameter andsaid rotatable ring-projecting beyond said diameter so as to besubjected to equal steam pressures on its opposite ends.

6. A packing for turbine shafts and the like according to precedingclaim 3 further characterized by means for yieldingly urg ing the tworings together.

7. A packing for turbine shafts and the like comprising a collar fast tothe shaft, :1 non-rotatable packing ring surrounding the shaft. arotatable packing ring interposed between said collar and non-rotatablering, and means interposed between said collar and rotatable ring foryieldingly urging the rotatable ring against the non -rotatable ring.the rotatable ring being balanced l0ngitudinally of the shaft withrespect to steam pressure thereon.

S. A packing for turbine shafts and the like comprising a collar fast tothe shaft, a non-rotatable packing ring surrounding the shaft, arotatable packing ring interposed between said colla' and non-rotatablering. said rotatable ring having a flange extending along the periphenvof said collar. and packing means betweensaid flange and said collar.the rotatable ring being arranged to be subjected to .-lll)SftllltltlllV no unbalanced steam pressure longitudinally of the shaft.

9. A packing for turbine shafts and the like comprising a sleeve fast tothe shaft. means at the outer end of said sleeve for packing the spacebetween the sleeve and shaft. a non-rotatable packing ring surroundingsaid sleeve. a rotatable packing ring interposed between said collar andnon-rotatable ring. and means interposed between said collar androtatable ring yieldingly to urge the rotatable ring against thenon-rotatable ring. the rotatable ring being balanced longitudinally ofthe shaft with respect to steam pressure thereon.

10. A packing for turbine shafts and the like according to precedingclaim 3, further characterized by means for supplying lubricantto themutually contacting surfaces of said rings.

11. A packing for turbine shafts and the like according to precedingclaim 3. further cln'iracterized in that the contacting surfaces of saidrings are radiall; curved.

12. A packing for turbine shafts like according to preceding claim 3,characterized in that the rings are ferentially continuous.

13. A packing for turbine shafts and the like comprising a packingmember rotatable with the shaft, and a non-rotatable packing memberfitting against the side of said r0 tatable member so as to preventsteam from escaping therebet ween. the rotatable member being arrangedto be subjected to no unbalanced steam pressure longitudinally of theshaft.

Signed by me at Boston. Massachusetts, this 30th day of July, 1918.

\VALTER F. SOMES.

and the further c1rcum-

